Journal of science and medicine in sport最新文献

Objectives: To examine associations between 24-hour movement composition in primary school-aged children and later BMI, quality of life, and behavioural outcomes, and to assess the impact of reallocating time between behaviours.

Design: Longitudinal study.

Methods: Data from waves 3, 6, and 7 of the Longitudinal Study of Australian Children (n = 2064; 47 % girls; aged 5 to 12) were analysed. Movement behaviours (screen time, sleep, and physical activity) assessed at ages 5 and 10 were treated as exposures, and follow-up outcomes at ages 10 and 12 included BMI, health-related quality of life (PedsQL), and behavioural difficulties (SDQ). Compositional data analysis examined the longitudinal associations between movement behaviour composition and these outcomes, whilst isotemporal substitution analysis estimated the effects of reallocating 30 min between behaviours.

Results: Compositional analysis showed that higher screen time at age 5 was associated with higher BMI, lower quality of life, and more behavioural difficulties at ages 10 and 12. In contrast, more physical activity and longer sleep at age 5 were associated with lower BMI, higher quality of life, and fewer behavioural problems later in childhood. Isotemporal substitution analysis revealed that replacing 30 min of screen time with physical activity or sleep improved outcomes: lowering BMI, enhancing quality of life, and reducing behavioural difficulties at follow-up.

Conclusions: Shifts in daily movement behaviour composition are associated with key health outcomes in children. These findings support the need for integrated public health strategies that reduce screen time, encourage physical activity, and promote healthy sleep to improve well-being.

Objectives: To investigate associations between physical activity volume during pregnancy and early postpartum with musculoskeletal conditions, specifically urinary incontinence, pelvic organ prolapse, and lumbopelvic pain.

Design: Prospective cohort study.

Methods: Data from the Queensland Family Cohort study (2018-2021) were analysed. Physical activity at 24- and 36-weeks' gestation, and 6 weeks postpartum was reported using a modified Active Australia Survey. Participants were categorised into nil to low (0-<500 metabolic equivalent of task [MET]·min/week), moderate (500-<1000 MET·min/week), or high (≥1000 MET·min/week) volumes. Symptoms of urinary incontinence, pelvic organ prolapse, and lumbopelvic pain were collected at corresponding timepoints. Associations between physical activity volume and musculoskeletal outcomes were examined using generalised estimating equations, adjusting for maternal age, pre-pregnancy weight, parity, and delivery mode.

Results: Nil to low physical activity was associated with greater pelvic organ prolapse severity (p = 0.002), but not with urinary incontinence or lumbopelvic pain. Gestational period was the strongest predictor of symptom severity across all outcomes (p < 0.001), peaking at 36-weeks' gestation and decreasing by 6 weeks postpartum. Parity and pre-pregnancy weight were predictors of urinary incontinence and lumbopelvic pain (p < 0.001), maternal age for urinary incontinence (p = 0.021), and delivery mode for urinary incontinence and pelvic organ prolapse (p < 0.001).

Conclusions: Physical activity volume was not significantly associated with urinary incontinence or lumbopelvic pain; however, nil to low physical activity was associated with increased pelvic organ prolapse symptom severity. Moderate physical activity during pregnancy may support optimal lumbopelvic musculoskeletal health.

Objectives: To examine changes in proximal patellar tendon structure during the adolescent growth spurt in athletes.

Design: Prospective observational study.

Methods: 173 adolescent athletes aged 11-15 years from specialised sporting programmes were recruited. Data collection occurred biannually for 2.5 years. Chronological age and maturity offset were calculated. Patellar tendons were scanned using ultrasound tissue characterisation, the proximal attachment was classified as having a hypoechoic area absent/present, and structure was quantified into four distinct echotypes (I-IV). Generalised additive models and generalised additive mixed modelling assessed associations between changes in echotype proportions and chronological age or maturity offset.

Results: 147 of 173 participants had normal tendon structure (i.e., no hypoechoic area) at baseline and across the study. In these tendons, a stronger linear association with maturation offset, but not chronological age, was observed for all echotypes suggesting a subtle improvement in tendon structure (p ≤ 0.01). Nine tendons (n = 8 participants) were hypoechoic at baseline and had a significant association with maturation offset and aligned tendon structure (echotype I; p ≤ 0.01) but not for disorganised tendon structure (echotypes III, IV; p = 0.6). Another 17 tendons (n = 15 participants) developed a hypoechoic area across the study.

Conclusions: Proximal patellar tendon structure undergoes echotype changes during adolescence, which was linearly associated with maturity offset and not chronological age. Areas of disorganised patellar tendon structure in adolescents at baseline appeared unchanged despite continued exposure to high loads. Skeletal maturation appears a critical period in the development of a normal and abnormal, proximal patellar tendon attachment having implications for patellar tendinopathy prevention.

Objectives: To examine the dose-response relationship between moderate-to-vigorous physical activity (MVPA) and sitting time trajectories with cardiac and all-cause mortality in a cohort of middle-aged and older-adults after a diagnosis of coronary heart disease (CHD).

Design: This prospective cohort study comprised Australian participants aged ≥45-years with CHD (2006-2020) who had self-reported MVPA (min/wk) and sitting time (hr/day) data from at least two survey waves.

Methods: MVPA and sitting time trajectories were categorised as remaining high, decreasing, increasing, and remaining low. Cardiac and all-cause mortality were the main outcomes. Associations were explored using Cox regression models.

Results: The cohort included 9430 participants (mean (SD) age, 70 (10) years; 3557 females (38 %)). During a median follow-up of 4.4 (IQR, 6.1) years, 540 cardiac and 2843 all-cause deaths were recorded. Compared with individuals that remained inactive, remaining active was associated with a 36 % and 49 % lower risk of cardiac and all-cause death, respectively. Decreasing or increasing MVPA over time was associated with a 20-33 % lower risk of all-cause death. Compared with high sitting time, individuals that maintained low sitting time or decreased their sitting time over time reduced the associated risk of cardiac and all-cause death by 33-38 %.

Conclusions: Regardless of pre-CHD diagnosis movement behaviours, individuals' post-CHD diagnosis can reduce their risk of cardiac and all-cause mortality by achieving the physical activity thresholds at any time and reducing their sitting time over-time. Further research is needed to confirm the physical activity and sitting time thresholds to receive these benefits.

This study examined the associations between time of day, handgrip strength (HS), and gait speed using data from 10,785 participants. HS was higher in the afternoon (+0.4-0.5 kg) and evening (+0.9-1.0 kg) compared with the morning, and higher in the evening (+0.5 kg) compared with the afternoon. Time of day (hour) was positively associated with HS (β = 0.06 kg). No significant associations were observed for gait speed. In conclusion, HS was lowest in the morning, higher in the afternoon, and greatest in the evening. These results underscore the importance of considering time of day in HS assessments.

This study examines concussion knowledge, attitudes, and behaviors among European American football athletes using an online survey. Data from 256 players (mean age 26.8 years (SD 4.9); 7.4 (SD 4.5) years of experience) across some of the highest leagues (Austrian Football League, German Football League, European League of Football) revealed an average concussion knowledge index of 17.9 (SD 2.3) of 25 and an attitude index of 63 (SD 6.3) of 75. Notably, 43.1 % of athletes reported they would continue to play despite experiencing concussion symptoms indicating a gap between knowledge, attitudes, and safe behavior. These findings underscore the need for targeted educational measures to improve the transfer of knowledge toward safer decision-making processes and to strengthen the prevention and management of concussions.

Objectives: To systematically analyze potential head injuries in professional international women's football between 2021 and 2024.

Design: Video analysis.

Methods: All match footage from the 2021 Women's Olympic Football Tournament, 2022 Union of European Football Associations European Women's Championship, 2023 Fédération Internationale de Football Association Women's World Cup, and 2024 Women's Olympic Football Tournament was reviewed. Potential head injuries, defined as when a player stayed down on the ground for more than 5 s and/or indicated that they were injured, with the body area involving the head, were coded using frame-by-frame video analysis to record player actions, visible signs of possible concussion, medical assessment, and injury outcomes.

Results: Across 147 matches, 362 potential head injuries occurred (2.46 per match; 72.2/1000 match hours). In total, 131 potential head injuries (36.2 %) were medically assessed, and 12 (3.3 %) resulted in immediate substitution. Visible signs of a possible concussion were seen in 84 players (23.2 %), with motor incoordination present in 10 cases (2.8 %). Medical assessment was performed in 61 (72.6 %) of cases with visible signs. The majority of potential head injuries (n = 251, 69.3 %) were from opponent direct contact, followed by ball-related contacts (n = 48, 13.3 %, 35 unintentional ball-to-head impact, and 13 headers). Aerial duels (45 %) were the most common action leading to a potential head injury.

Conclusions: Opponent direct contact was the most frequently observed mechanism of a potential head injury. While the majority of players with visible signs of possible concussion received medical assessment, continued concussion awareness to support medical teams in improving the identification of incidents with potential head injuries is recommended, with a potential for the inclusion of visible signs of a possible concussion to facilitate an on-field medical assessment of players.